Rotary-kiln feed-control system



Gat. l5, 1929.

W. R. BENDY ROTARY KILN FEED CONTROL SYSTEH Filed July l.' 1927 ,if .59. @Q i "II f NIU f. :grill k\ 5H N x .s f; N

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` ffm/en m )Wfwmy l?. fiend/1y ji?? www5! Patented Oct. l5, 1929 i UNITED STATES WIL'FED B. BENDY, OF CICAGO, ILLINOIS munir-nun FEED-concreet. srs'rmr Application led July 1, 1927. Serial No. 202,905.

The invention relates to a kiln control, and l it is an object of the invention to establish functional uniformity between the feed drive of a kiln and the drive of kiln itself.

In the manufacture of cement or in the conversion of other materials, it has been shown that a kiln, althonghjit maybe driven by a constant source of powers-varies its rotary speed, depending upon the load or the charge traveling through the same. If, however, upon a variation of this speed the supply of raw material isv continued at the same rate as before, the condition of over-charge or under-charge ofthe kiln will be established. It

ra has been an object of installations in cement factories to attain a roportionate uniformity of the speed of the eed drive with the drive of the kiln. For this purpose expensive and cumbersome transmission s stems were in- 2o stalled between the feed drive and the kiln drive, systems which were not only costly, but owing to the length of the kiln and the distance between the oints to be controlledwere dicult to maintain and gave rise to numerous disturbances in the operation. Itis an object of the present invention to overcornethese drawbacks by introduca van electric control system in the drive of the eed and' to render this electric control system de- :s0 ndent upon the-rate of speedatwhich the riln operates. l 'f An object of the invention is to 'provide a u feed control for kilns in which the rate of feed is varied in acordance with the variations'in the rate of the kiln operation without, however, necesitating any variation inthe runnin speed of the prime mover drivin the feed.

It is furthermore an object of e invention to intermittently interrupt the drive of the feed by varying certain electric connections when for any reason the drive of the kiln is lreduced in speed. f

Another object of the invention is to provide a kiln control system in which prime mover for the drive of the feed is automati cally and intermittently interrupted in accordance with variations in the speed of the` kiln, the duration of the periods of interruption varying also in dependence upon the rate W of speed of the kiln.

The invention also has the object of intermittently. interruptin the driving connec tion between the 'fee and its prime mover by releasing a clutch interposed between thesev two elements of the installation, and the operative or inoperative position respectively of 'l the clutch being partly dependent upon the variations in the drive ofthe kiln.

This invention also has the object of inten! rupting a current supply to an electrically -op- 6o a ,erable mechanism in the drive of thefeed, the

interruption setting in at predetermined times relative to the drive of the feed, and teru minating after intervals controlled by the drive of the kiln. y

The invention also has the object of pro.- viding an electric control system with a rapidly acting automatic switch device for interrupting or establishing respectivel certain circuit connections on the feed si e of the system. A Y Another object is to improve the efficiency of kilns in which the speed control for the .feed is dependent on the speed control of the kiln, enabling the operator to feed a more constant load to the kiln than would he pos-, sible if dependence on his judgment was re lied on only.

Another object is to provide a kiln control fsystem in which the amounts of material fed 30' r revolution of the kilny may be deintelyized and may be .changed when necessary without permittig any immediate alterations l vof the rate effe With these and numerous'other objects in w gl'view, an embodiment oi the system is illus tratcd in the accompanying drawings, whcre i l. Fig.'1 is adiagramrnatic section through a kiln drive showing-fits feed system, certain parts of the installation being shown in ele` valon;

electric connections; ,1

. 951 Fig. 3 is a front elevation` of a quick acting another position and on a larger scale; 1w

rig. 2 is a @ncaa 'ds-glam a insalate.

` Fig. is a detail sectional view along line '5-'-5 of Fig. 3, and v v Fig'. 6 isa detail sectional elevation on line 6--6 of Fig. 3.

The rotary kiln 1`is shown as being supported by bearing rollers 2 in an approved ordesired way, and it receives its drive through a shaft 3 carrying a pinion 4in mesh with the gear rim 5 which is secured about the drum or kiln.

A rotary feed system is shown by wa of example in Fig. 1 as being of the type o the Ferris wheel feed, although it is obvlous that any other desired type of -feed may be em-l ployed, and this drive contains an electrically operable mechanism. An electric motor 7, preferably operating at constant speed,

rives b means of a'clutch 8 a reduction gearing enc osed .in a housing 9, the details of which are not of importance for the present application. The driven shaft of the reduction gearing 9 carries .the feeding Ferris wheel 11 which is supported to travel through a tank 12 for'continuously lifting approximat-ely uniform quantities of the slurry from the tank and depositing the same into the hopper 14 from which a chute 15 delivers this material into the interior of the kiln 1.-

For the purpose of automatically controlling the feed, electric means are provided, these electric means beingin cooperation, in the present system, with thel clutch 8, which may be a-magnetic clutch, adapted to enter into operative position when electric current is supplied to a coil, not shown, mounted in one of the clutch elements. Clutches of this ype are known, to those skilled in the art, and

o not require any detailed description.

Thel supply of current to this clutch, orthe interruption of the current supply 4respectively, 1s under the control of a quick act- .ing automatic switch associated with the drive of the kiln and another switch serially con- -nected to the same and located in the drive of ther feed. The switches are indicated in general at 16 and 17 respectively, and preferably are of identical construction. In the following s ecification detailed reference is chainV 24 and sprocket 27, while the housing v18 divided b into acom artment 20 or the actuating mech'-A made, there ore, to one of these switches only. l The switches 16 and 17 'each comprise a a partition wall 19 anism an a compartment 21 for the switchr mechanism proper.- The actuating mechanism comprises a pinion 23 suitably support ed in the housing'and driven in the switch 17 from the shaft 10 by means of a sprocket inion of the quick actmg switch 16associate with thekiln 1 may be driven by an extension 25 of. the drive shaftv 3.

.The pinion 23 is in drivingengagement With a gear 26 supported in the housing 18 and having an eccentric or crank pin 29 to which a crank rod 30 is secured so as to be lthe lever.

rotatable thereon. This crank rod 30 is inl functional connection intermediate its ends with a connecting lever 31, the connection being effected by a square collar .32 slidable on the crank rod 30. This collar has trunnions 33 and 34- by means of which it is pivotally supported on the lever 31 and on a bracket 35 secured to said lever, Fig. 6.

At a relatively great distance from this connection with the crank rod 30, the lever 31 is pivotally secured near its end to the housing 20, the lever being provided with an opening 36 through which a nin 37 extends, the pin being non-rotatable connected with Trunnions 38 and 39 res ectively projecting from the ends of the pin nd their pivotal support in bore 40 of the boss integral with the housing, and in a'bearing strap 41 respectively secured to lugs 42 and 43 which also form a part of the housing.

Normally transmission of anv movement from the connecting rod 30 to the switch actuatinfr lever 31 is prevented owing to the provision of a locking device which acts upon the switch lever 31 and which in the embodiment illustrated is formed by a head 44 carried at the free end of the lever, and provided with two notches 45 and 46. A tooth 47 is secured to another spring controlled lever 48 and is adaptedto enter either of th(` notches 45 or 46 to hold the lever 31 against movement, while the crank rod 30 slidably ex- .tends through the souare collar 32 which is rocked in the lever 31 thereby.

The longitudinal displacement of the crank rod 30 relatively to the collar 32 serves for alternately compressing' springs 49 and 50 respectively which surround the crank rod 30, and which are interposed between the collai` 32 and upper and lower fixed collars 51 land 52 respectively secured to the crank rod 30.y

The lever 48 which carries the locking tooth 47 is pivotallyv mounted inthe housing at,53 and is provided with an angular arm 54 having a cam edge 55 adapted to project into the -path of'either of two rollers 0r pins 56 secured to the rotary ear 26 at fixed angular spacings. In the illustrated embodiment, these rollers are shown to be spaced 180. The cam lever 48 also is provided with an extension 57 to which the end of a spring 58 is connected, the opposite end being anchored to a pin projecting from the casing. Upon arrival of one of these rollers 56 in va position -to depress the cam edge 55, the lever 48 will be rocked about its pivotal support 53 Vagainst the action of the spring 58, and will thereby withdraw the locking tooth 47 fromengagement with the notch 45 or 46 respectively in the head 44 of the lever 31. Immediately after the passage of the roller 56 over the cam edge 55, the lever willbe returned to the position indicated in Fig. 3 by the spring 58,"

thereby a ain presenting the cam edge 55 in the pat Vof the next roller.

Owing to the tension applied to either of the springs 49 or 50 by the crank rod 30,

the lever 31 will be rapidly thrown from one terminal position to the opposite terminal position, the upward movement of the lever being supported by another spring 59 connected With the' lever 3l and a-nchored at one end in the casing.

From the above description it will be clear that with each passage of a roller 56 over the cam a sudden reversion of the position of the lever 31 will occur, and that this lever will not be permited to occupy any intermediate position, but that upon arrival of the lever in its terminal position, it will immediately be automatically locked through the entry ofthe tooth 47 in either one of the notches 451er 46 at the head of the lever. l

The lever 31 is firmly united in the second compartment 21 of the housing with a removable bracket 60 to which the switch' blade 61 is secured. The free end of the switch blade carries contact plates 62 adapted to engage stationary contacts 63 and 64 mounted on a suitable insulating block 65 in said compartment. The inclination of the bracket '60 relatively to the lever 31 is such that the switch blade 61 is forced under tension against the respective contact against which itrests, so as to maintain suitable conductive engagement with the respective contact.

The two automatic switches 16 and 17 are y serially connected in the electric current, as illustrated in Figures 1 and 2. It will be seen that of the conductors and 71 supplying the current to the control system, one isfconnected to the electrically operable `mechanism,I namely the clutch 8, (which clutch usually contains an energizing coil), While the other conductor leads to the switch blade 61 of the switch 16=Which is associated with the kiln drive. The contacts t63 and 64 of the kiln drive switch 16 are connected 'with the corresponding contacts 64 and 63 respectively of the switch 17 for the feed drive by the conductors. The outgoing lead from the energizing coil of the clutch is attached to the blade .61 of the feed drive switch 17.

supply to the electrically operable mechafy vnism will be interrupted. This mayoccur,

for instance when-owing to the constant speed drive of the feed switch 17, the blade 61 of the` same is thrown into engagement with the stationary contact plate 63 While the switch blade 61 of the kiln drive switch 16 remains' still in engagement with its contact 63. This will occur when for instance the load on the kiln is so heavy that rotation of the samevis retarded relatively to the normal speed. The proper relation for the supply of current to the clutch 8 will only be resumed whenthe kilndrive switch 16 in the continued operation of the kiln is moved through rotation of the gear 4 to conductive osition with respect to the contact 64, in w ich case, thecurrent supply for the clutch' 8 is again established and the `drive of the feed again is initiated. y

The speed relations` are such that when the kiln 1 is operating at the maximum speed for which it 1s designed, the feeder will operate at a speed about ten per cent higher than would be the casein the usual installation. The switches govern the operation of the magnetic clutch, and hence, although the feeder operates ata fixed speed when running, this feed is interrupted for periods of a length dependent upon the speed of the kiln, and hence the feed makes a certain predetermined number of revolutions for each revolution of the kiln, Whatever the speed of the latter may be. rIhe maximum kiln speed may for instance be two revolutions per minute, and the ratio of kiln speed to feeder speed may be 1 to 10. Therefore, when the kiln is operating at full speed, two revolutions per minute, the feeder "will revolve twenty times within the period of one minute, but of this period of one minute, fifty-four seconds only are used by the running period of the feeder, and durin the remainder, of six seconds of this peri the feeder is at rest. When the kiln is operating at half speed, or onerevolution per minute, the feeder will revolve twen ty,` times in two minutes, but ofthis period of ltltl two minutes, ifty-four seconds only are used byj the running period, and it will remain at rest for the remainder of sixty-six seconds.

From the above description, ittwill be ohvious that 'in-this control system, the necessity of` cumbersome connections i between the drives of the kiln and feeder are entirely obviated, that lin spite of this condition, how'- ever, a proportionate control of the feed .in respect of the drive of the kiln is obtained, and that the prime mover for the feed may be a continuous uniform speed motor cf` standice ard construction runningat the desired speed all the time. Itis, ever, that instead of a motor running at practically uniform speed continually'and effectM ing the drive of the feeder through the interposition of a clutch, vthe switch connection may be placed in the leads connecting the mo. tor with the supply, and that, therefore the furthermore, obvious how- Y las erated means mechanically Y. drive ofthe motor may be interrupted at intervals. The claims are contemplated to includel any intermittent interru tion .ofthe current supply to an electrica ly operable ,f5 mechanism in the drive of the feed.

v Claims:

1. A kiln feed control comprising an electrically operable mechanism in the drive of the feed and mechanically actiated by said gdrive, and electrical means mechanically ac- 'tuate'd by the drive of the kiln for varying the termination of intervals of energization of said electrically operable mechanism in predetermined relation to the speed ofthe kiln.

I u drive and a kiln drive, the feed drive being 2.v A kiln feed control, including a feed operable at a fixed speed, and electrically opassociated with said feed drive and said iln drive for inm terrupting the drive of the feed for intervals of time determined by the variation of the rotary speed of the kiln.

3. A kiln feed control, comprisin a motor driving the feeder, a clutch on t e feeder drive shaft interposed between' said-motor and feeder, a drive for the kiln, and means 4mechanically controlled by the speed of the kiln for intermittently rendering said clutch inoperative.

to 4. A kiln feed control, comprising an .electrically operable mechanism for the feedy drive and mechanically associated with said drive, and electrically operated means in the driveof the kiln andn'iechanicallyI controlled by the kiln for intermittently interrupting the current supplyA to said 'electrically operable 1 mechanism.

l '1- ,5. A kiln feed control, comprising a feed- 7. A kiln feed control, comprising a feeder, an electrically operable mechanism in the 1' drive of tliesame, means in the drive of the M feeder for interrupting the current supply to said electrically operable mechanism at redetermined intervals, and means in the drive of the kiln for reestablishing the current supply to said electrically operable mechanism, said lastnamed means being dependent in `their operation upon the speed of the kiln.

8. A kiln feed control,com rising a switch actuated by the drive of the ki n, an electrically operable mechanism in the drive of the 6. A kilnfeed control, comprising a feedforfreestablishing the current supply to said electrically operable mechanism.

feed, and a switch actuated thereby and serially connected with said first named switch in such manner that current can be supplied to the electrically operable mechanism only when each of said switches is in a predetermined position.

9. A kiln feed control, including a drive for the feed containing electrically operable mechanism, a switch iii the current supply of said mechanism, another switch serially connected with said rst named switch in the drive of the kiln, and means for rapidly ac-` tuating each of said switches independently of the other by the drive pertaining to the same. v

10. A kiln feed control comprising a feed drive with an electrically operable mechanism, a switch in the current supply of the electrically operable mechanism and containin a rotary switch actuating member, a switch lever associated with said rotary switch actuating member, means for .locking the switch lever against movement, and means under control of said rotary switch actuating member for releasing said switch lever.

11. A ln'ln feed control comprising a kiln feed drive containing electrically operable mechanism, a switch in the current supply for said mechanism, a rotary switch actuating member driven by the feed drive, a switch lever, means independent of said rotary actuating member for locking the switch lever against movement, means under control of i said rotary switch actuating member for releasing the switch lever from the lock, and independentv means for rapidly actuating said switch lever to change its position relatively to the current supply.

12. A kiln feed control comprising a feeddrive with an electrically operable mechanism, a switch in the current supply of said electrically operable mechanism, a rotary switch actuating member operated by said drive,.a switch lever under control of said actuating mechanism, al locking device for said switch lever, means under control of the .rotary actuating mechanism for lintermitreleasing said locking device, means tentl for t rowing the switch lever from one terminal positionl to another terminal position upon release, and independent means for returning the locking device to operative position in thenew position of said switch lever.

13. A kiln feed control comprisinga motor driving the feeder, means for driving the kiln and mechanisms mechanically associated with both of said driving means and dependent upontlie speed of the kiln for varying the drive of the feeder in predetermined relation to the rotary speed of the kiln.

14. A kiln feed control, comprising in association with the driving means for the feeder and in association with the driving means for the kiln, automatic electric means directly menace connected mechanically to said two 'tlrivin menne reepectively, for varying' the interva of operation of the feeder 1n redetermined relation to the rotary spee of e kiln. 15. A lriln` feed control comprising in com bination with the drive of the kiln, an e1ec trically operable mechanism in the drive of the feeder, directly connected mechanically with4 seid drive, and means for var g the w operation of said electrically operablznmechanism in accordance with the rotary feed of the kiln.` j l 16. kiln fecd'control com risin in di l rect mechanicalconneetion Witx the rive of mi the eecl, an electrically o erable mechanism und kiln actuated means dlpending u on theretar speetl of the kiln and electrica y associnte with eaicl mechanism for varying the intervalle ci energization of said electrically mi cperelele mechanism.

In testimony whereof-I allin- -my signature et l@ South La Salle Street, Chica o Illinois. y menen n, einem4 le I fle 

